This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. NLSL is a non linear least squares program for fitting CW spectra based on microscopically order but macroscopically disorder (MOMD) model. NLSL.SRLS is a non linear least squares program for fitting multi-frequency CW spectra based on slowly relaxing local structure (SRLS) model A service request was received from Dr Vibha Bansal on the usage of the NLSL and NLSL.SRSL programs from ACERT website to study active site dynamics of Subtilisin Carlsberg by SDSL ESR.